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Up Topic Rybka Support & Discussion / Rybka Support / Perpetual check position with score 120 in PV
- - By rwbean [au] Date 2010-05-31 03:00
Here is the file I'm using as Rybka 4 input (a variation from Kasparov vs the World with 27. h4)

uci
setoption name Hash value 1024
position startpos moves e2e4 c7c5 g1f3 d7d6 f1b5 c8d7 b5d7 d8d7 c2c4 b8c6 b1c3 g8f6 e1g1 g7g6 d2d4 c5d4 f3d4 f8g7 d4e2 d7e6 c3d5 e6e4 d5c7 e8d7 c7a8 e4c4 a8b6 a7b6 e2c3 h8a8 a2a4 f6e4 c3e4 c4e4 d1b3 f7f5 c1g5 e4b4 b3f7 g7e5 h2h3 a8a4 a1a4 b4a4 f7h7 e5b2 h7g6 a4e4 g6f7 b2d4 f7b3 f5f4 h3h4 e4f5 b3b1 f5f7 b1e4 d4e5 f1b1 d7c7 e4a4 e5d4 b1c1 d4b2 c1c6 b7c6 a4a7 c7c8
go infinite

and here are the last lines of output with scores.

info depth 28 score cp 120 time 708386 nodes 363913435 nps 513721 pv a7b6 b2e5
b6c6 c8d8 c6b6 d8d7 b6b7 d7d8 b7a8 d8d7 a8b8 f7h7 b8a7 d7d8 a7b6 d8d7 b6a7 d7d8
a7b6 d8d7 b6a7 d7d8 a7b6 d8d7 b6a7 d7d8 a7b6 d8d7 b6a7 d7d8 a7b6

info depth 29 score cp 121 time 1357850 nodes 663138261 nps 488373 pv a7b6 b2e5
b6c6 c8d8 c6b6 d8d7 b6b7 d7d8 b7a8 d8d7 a8b8 f7h7 b8a7 d7d8 a7a8 d8d7 a8a4 d7e
6 a4a2 d6d5 a2a6 e5d6 g5f4 h7b1 g1h2 b1b4 a6c8 e6f7 c8f5 f7e8 f4d6

I'm ok with the depth 29 line, but the depth 28 line looks like a repetition by perpetual check, so why would it be evaluated at +120?  What should I believe, the repetition or the score?
Parent - By Vasik Rajlich (Silver) [pl] Date 2010-06-04 15:01
You should believe the score. The PV is reconstructed from the hash table and can be incorrect.

Vas
Up Topic Rybka Support & Discussion / Rybka Support / Perpetual check position with score 120 in PV

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